Have you noticed the G1 and G2 both share one common physical trait? Yeah, they both have chins. And there's a reason for it *cue in Bernard Herrmann's Vertigo music*

According to HTC: Personality. The Androids are like people, they have chins, they have personality. The other reason: They also have protruding nippleballs: Having a chin allows the HTC engineers to pull the trackballs out more than competing devices, making them easier to use while protecting them with the chin.

There you have it. Now you'll be able to sleep tonight.